I'm still confused; any more help with the following is appreciated...(hope I can understand it!)Using Warder's grammar and other sources, the -a.m ending of present participles is used in nominative, as you say. Since the pres. part. is added to the verb stem, where did the 'y' come from in passambhaya.m? Wouldn't it be passambha.m or passambhanto in nom. masc. sing.? Even so, kaayasankhaara.m is not nominative, it's accusative, and Warder's table (p.46) does not show '-a.m' as a possible accusative ending for pres. part. agreement here, it shows -anta.m (making passambhanta.m). And why is the accusative used here anyway? Surely it doesn't indicate what is being breathed in!Maybe this is way too advanced for me right now when major scales and power chords are still challenging... ......Okay, I just found enough answers to let me sleep tonight."441. Verbal bases ending in e (1st Conj. 3rd. Division; 7th. Conj. and causal bases. See "Derivative or secondary conjugation") which have also another base in aya take only the termination nta after the base in e, and both ota and µ after the base in aya."http://www.tipitaka.net/pali/grammar/chpt10.htm

I had assumed this participle was from passambhati instead of passambheti, and didn't know the pali gerund/absolutive is indeclinable.

You found the correct answer. Passambhaya.m is the present participle (-a.m) of a causative (-aya-) - I should of course have mentioned that. I'm happy to see that you got a good night's sleep!

Pali has a beautiful economy of expression. In one word - here: passambhaya.m - it is possible to express something that needs a whole phrase in the Western languages.

“Body”: There are two bodies—the mentality-body and the materiality-body.

Feeling, perception, volition, sense-impression, attention-mentality and the mentality-body—and those (things) which are called the mental formations—this is the mentality-body.[77]

The four great primaries and the materiality derived from the four great primaries—in-breath and out-breath and the sign for the binding (of mindfulness)—and those (things) which are called the bodily formations-this is the materiality-body.

!! It looks like Russian is closer to Pali than English is--looks like..."As Gurdjieff explained to Ouspensky ... "for exact understanding exact language is necessary." In his first series of writings, Gurdjieff explains how difficult it is to choose an ordinary language to convey his thoughts exactly. He continues..."the Russian language is like the English...both these languages are like the dish which is called in Moscow 'Solianka' [solyanka], and into which everything goes except you and me..."